Hi Bob:

See below for your answers:

As indicated in another thread, we will be relocating sometime in 2007. We are considering a switch to VoIP or Vonage for all our local & long distance needs. We don't intend to make this change until we move.

Some questions...

- When considering Internet telephony, is there a performance difference between Cable high speed and DSL?
Performance of Cable with depend on the density of the netweork where you are going to be residing, while for DSL, you will surely get what they tell you
- Other than Vonage, what other VoIP providers should we consider?

Vonage is by far THE Best, I have personally used it for the last 2 years, and I have been able to take my equipment to 5 different countries and use it to call back home in US without any problem (everywhere all I needed to do was hook it into my Hotel's highspeed connection, its SO much more economic than depending on these exotic International calling plans.
- Among the competing VoIP providers, what are the main differences between them?
Price and technology, like I said, by far Vonage is THE BEST
- What are people saying about these services; are they happy or have any concerns?
People will always have diverse views, I think you would know that
- Is there any compelling reason we should hold off selecting VoIP until some point in the future such as pending regulation/approval of other technologies?
Patent fights happen all the time in the corporate world, this should not affect the services provided anyway, as long as you pay your bills, and get your service why would you care what that company's logo color is. Corporates play all kinds of gimmicks to confuse the consumer and trap them in one way or the other.
Thanks for your input.

Personal Disclaimer: What I have mentioned here is soley my point of view, and I would encourage the reader to use their own judgement in making any decisions, and please don't hold me responsible for your decisions.

Cheers

-Sreehari